Tire Size Box

225/40R16 vs 225/50R16

225/50R16 compared with 225/40R16

+7.7% diameter, 0.0" width

225/50R16 is 24.86" tall vs 23.09". More than the 3% rule of thumb, so check carefully before switching.

23.1"16" rim3.5"8.9" wide
225/40R16 (solid) compared with 225/50R16 (dashed outline), drawn to scale

With 225/50R16 tires, when your speedometer says 60 mph you are really going

64.6 mph

225/50R16 is +1.77 inches (+7.7%) in overall diameter. That is more than the 3% most shops and makers recommend.

225/40R16225/50R16Difference%
Overall diameter23.09"24.86"+1.77"+7.7%
Section width8.86"8.86"0.00"0.0%
Sidewall height3.54"4.43"+0.89"+25.0%
Circumference72.53"78.09"+5.57"+7.7%
Revolutions per mile873.6811.3−62.3−7.1%

Speedometer difference

If your vehicle came with 225/40R16 and you fit 225/50R16, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph21.5 mph+1.5 mph
30 mph32.3 mph+2.3 mph
40 mph43.1 mph+3.1 mph
50 mph53.8 mph+3.8 mph
60 mph64.6 mph+4.6 mph
65 mph70.0 mph+5.0 mph
70 mph75.4 mph+5.4 mph
75 mph80.8 mph+5.8 mph
80 mph86.1 mph+6.1 mph

Each size on its own

Questions

Which is bigger, 225/40R16 or 225/50R16?
225/50R16 is taller by 1.77 inches (24.86" vs 23.09"). 225/40R16 is the same width.
Can I replace 225/40R16 with 225/50R16?
It is not recommended without checking carefully. The diameter difference is +7.7%, more than the 3% most shops and makers allow. It will throw off the speedometer and may affect ABS, stability control and clearance.
How much will 225/50R16 change my speedometer?
When your speedometer reads 60 mph with 225/50R16 fitted (calibrated for 225/40R16), your real speed is 64.6 mph. Your odometer will under-count miles by about 7.7%.
Will 225/50R16 lift my vehicle?
Ride height changes by half the diameter difference: +0.89 inches of ground clearance at the axle.

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